org.apache.hadoop.hive.common

Interface ValidWriteIdList

All Known Implementing Classes:

ValidCompactorWriteIdList, ValidReaderWriteIdList

public interface ValidWriteIdList

Models the list of transactions that should be included in a snapshot. It is modelled as a high water mark, which is the largest write id that has been committed and a list of write ids that are not included.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	ValidWriteIdList.RangeResponse The response to a range query.

Field Summary

Fields

Modifier and Type	Field and Description
static String	VALID_WRITEIDS_KEY Key used to store valid write id list in a Configuration object.

Method Summary

Modifier and Type	Method and Description
long	getHighWatermark() Get the largest write id used.
long[]	getInvalidWriteIds() Get the list of write ids under the high water mark that are not valid.
Long	getMinOpenWriteId() The smallest open write id.
String	getTableName() Get the table for which the ValidWriteIdList is formed
boolean	isValidBase(long writeId) Returns true if such base file can be used to materialize the snapshot represented by this ValidWriteIdList.
boolean	isWriteIdAborted(long writeId) Indicates whether a given write maps to aborted transaction.
ValidWriteIdList.RangeResponse	isWriteIdRangeAborted(long minWriteId, long maxWriteId) Find out if a range of write ids are aborted.
ValidWriteIdList.RangeResponse	isWriteIdRangeValid(long minWriteId, long maxWriteId) Find out if a range of write ids are valid.
boolean	isWriteIdValid(long writeId) Indicates whether a given write ID is valid.
void	readFromString(String src) Populate this ValidWriteIdList from the string.
String	writeToString() Write this ValidWriteIdList into a string.

Field Detail

VALID_WRITEIDS_KEY

static final String VALID_WRITEIDS_KEY

Key used to store valid write id list in a Configuration object.

See Also:

Constant Field Values

Method Detail

isWriteIdValid

boolean isWriteIdValid(long writeId)

Indicates whether a given write ID is valid. Note that valid may have different meanings for different implementations, as some will only want to see committed transactions and some both committed and aborted.

Parameters:

writeId - write ID of the table

Returns:

true if valid, false otherwise

isValidBase

boolean isValidBase(long writeId)

Returns true if such base file can be used to materialize the snapshot represented by this ValidWriteIdList.

Parameters:

writeId - highest write ID in a given base_xxxx file

Returns:

true if the base file can be used

isWriteIdRangeValid

ValidWriteIdList.RangeResponse isWriteIdRangeValid(long minWriteId,
                                                   long maxWriteId)

Find out if a range of write ids are valid. Note that valid may have different meanings for different implementations, as some will only want to see committed transactions and some both committed and aborted.

Parameters:

minWriteId - minimum write ID to look for, inclusive

maxWriteId - maximum write ID to look for, inclusive

Returns:

Indicate whether none, some, or all of these transactions are valid.

writeToString

String writeToString()

Write this ValidWriteIdList into a string. This should produce a string that can be used by readFromString(String) to populate a ValidWriteIdList.

Returns:

the list as a string

readFromString

void readFromString(String src)

Populate this ValidWriteIdList from the string. It is assumed that the string was created via writeToString() and the exceptions list is sorted.

Parameters:

src - source string.

getTableName

String getTableName()

Get the table for which the ValidWriteIdList is formed

Returns:

table name (<db_name>.<table_name>) associated with ValidWriteIdList.

getHighWatermark

long getHighWatermark()

Get the largest write id used.

Returns:

largest write id used

getInvalidWriteIds

long[] getInvalidWriteIds()

Get the list of write ids under the high water mark that are not valid. Note that invalid may have different meanings for different implementations, as some will only want to see open transactions and some both open and aborted.

Returns:

a list of invalid write ids

isWriteIdAborted

boolean isWriteIdAborted(long writeId)

Indicates whether a given write maps to aborted transaction.

Parameters:

writeId - write id to be validated

Returns:

true if aborted, false otherwise

isWriteIdRangeAborted

ValidWriteIdList.RangeResponse isWriteIdRangeAborted(long minWriteId,
                                                     long maxWriteId)

Find out if a range of write ids are aborted.

Parameters:

minWriteId - minimum write Id to look for, inclusive

maxWriteId - maximum write Id to look for, inclusive

Returns:

Indicate whether none, some, or all of these write ids are aborted.

getMinOpenWriteId

Long getMinOpenWriteId()

The smallest open write id.

Returns:

smallest Open write Id in this set, null if there is none.